I had this problem. The fan motor in the weather head was going south. It was drawing more power than the USB port could provide. Scott Smith had me move to the USB 3 port and that worked for a while until the fan motor began to draw more power. Then even the 3.0 port couldn't help. Hell, I had everything turned off and the weather station quit reporting to the PC. Drove me nuts and Don Higgins nuts trying to help me out. I even bought a new computer. That didn't help. Trying to figure this out in the trailer I had the weather station set up in the trailer. I could smell burning electrics from it. So I bought a new weather station from Don and that fucking thing was defective. Finally, Don met me at an exit on I-75 with a new weather head just in case. Bingo! the new one worked just fine and continues to work fine.
A computer geek told me that when the power demand at the USB port exceeds it's ability to provide it the port quits working. It won't make a difference what you have turned off or on. My unit was older and I used it to death. It just wore out.
BTW, a phone call to Altronics told me that these weather stations draw 200 milliamps. I'm guessing mine was drawing more than the USB could handle.